This invention relates to a an oscillating toothbrush, and more particularly to a toothbrush which has its brushing surface move upwardly and downwardly as the brush moves across the surface of the teeth.
There has been provided a relatively simple construction for an oscillating toothbrush illustrated in U.S. Pat. No. 3,261,047 issued to W. Klang, entitled "Toothbrush" on July 19, 1966. This toothbrush discloses a cylindrical handle partially enclosing a shank to which there is attached opposite pins, the opposing pins cooperating with through helical slots in the body of the handle of the toothbrush. The brushing end of the shank is offset from the main shank portion and as the toothbrush moves across the teeth, the brushing surface acquires an up down brushing motion.
There is also disclosed an oscillating toothbrush of a more complex construction issued to S. Yusko, U.S. Pat. No. 2,660,745 entitled "Oscillating Toothbrush" issued on Dec. 1, 1953 in which a complex helical spring arrangement is provided and cooperation with a pin and helical slot construction. In this oscillating toothbrush, the brushing surface is not offset from the shank portion and the shank portion is entirely enclosed within the body of a handle held while the toothbrush is moved across the surface of the teeth.
The above mentioned Klang patent has the disadvantage that the open through slot provided for achieving the up and down motion of the brushing surface has the particular properties of picking up debris such as hair and the like which would cause the cooperating pin and slot members to become dirty, interfering with its proper operation. Further, the stop surface for the back and forth motion of the shank portion of the oscillating toothbrush of the Klank construction is the pin cooperating with the helical slots. Since the pin is of a relatively light construction, the forces imparted to the pin as it stops in both the front and rear portions, especially the rear portion can be excessive causing the pins to easily crack and break from the shank. In addition, the Klang construction has the distal end of the shank extending beyond the rear of the handle thus providing an unattractive appearance and further providing the dangerous possibility that the distal end as it moves in and out of the handle can cause injury to the user.
The prior Yusko construction generally is of a complex nature which is improved upon by the Klang construction and also does not effectively achieve the brushing operation. Further, the manner in which the Yusko brush can be assembled and the stop surfaces provided as well as effective cleaning action can all present significant problems in the Yusko construction.
An object of this invention is to provide an improved oscillating toothbrush in which the appearance is attractive, the cost of construction is low, and the operation is trouble free.
Another object of this invention is to provide such an oscillating toothbrush which can be effectively cleaned.
Yet another object of this invention is to provide such an oscillating toothbrush which can be easily assembled and also disassembled for cleaning of the various members of the toothbrush.
Still another object of this invention is to provide such as oscillating toothbrush in which the cooperating helical slot and pin member is achieving the oscillating motion or protected from foreign matter so as to prevent an unimpaired cooperating set of surfaces for achieving the oscillating function.
Yet another object of this invention is to provide such an oscillating toothbrush in which the pin member is prevented from shearing during its operation because of the force imparted to it as it approaches its rear stop position.
Other objects, advantages and features of this invention will become more apparent from the following description.